1 files changed, 30 insertions, 32 deletions

diff --git a/drivers/watchdog/imx_sc_wdt.c b/drivers/watchdog/imx_sc_wdt.c
index e9ee22a7cb45..1280b9b1ec2a 100644
--- a/drivers/watchdog/imx_sc_wdt.c
+++ b/drivers/watchdog/imx_sc_wdt.c
@@ -34,6 +34,7 @@
 
 #define SC_IRQ_WDOG			1
 #define SC_IRQ_GROUP_WDOG		1
+#define SC_TIMER_ERR_BUSY		10
 
 static bool nowayout = WATCHDOG_NOWAYOUT;
 module_param(nowayout, bool, 0000);
@@ -55,13 +56,34 @@ static int imx_sc_wdt_ping(struct watchdog_device *wdog)
 	return 0;
 }
 
+static bool imx_sc_wdt_is_running(void)
+{
+	struct arm_smccc_res res;
+
+	arm_smccc_smc(IMX_SIP_TIMER, IMX_SIP_TIMER_START_WDOG,
+		      0, 0, 0, 0, 0, 0, &res);
+
+	/* Already enabled (SC_TIMER_ERR_BUSY)? */
+	if (res.a0 == SC_TIMER_ERR_BUSY)
+		return true;
+
+	/* Undo only if that was us who has (successfully) enabled the WDT */
+	if (!res.a0)
+		arm_smccc_smc(IMX_SIP_TIMER, IMX_SIP_TIMER_STOP_WDOG,
+			      0, 0, 0, 0, 0, 0, &res);
+
+	return false;
+}
+
 static int imx_sc_wdt_start(struct watchdog_device *wdog)
 {
 	struct arm_smccc_res res;
 
 	arm_smccc_smc(IMX_SIP_TIMER, IMX_SIP_TIMER_START_WDOG,
 		      0, 0, 0, 0, 0, 0, &res);
-	if (res.a0)
+
+	/* Ignore if already enabled(SC_TIMER_ERR_BUSY) */
+	if (res.a0 && res.a0 != SC_TIMER_ERR_BUSY)
 		return -EACCES;
 
 	arm_smccc_smc(IMX_SIP_TIMER, IMX_SIP_TIMER_SET_WDOG_ACT,
@@ -180,19 +202,18 @@ static int imx_sc_wdt_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
+	if (imx_sc_wdt_is_running())
+		set_bit(WDOG_HW_RUNNING, &wdog->status);
+
 	watchdog_stop_on_reboot(wdog);
 	watchdog_stop_on_unregister(wdog);
 
-	ret = devm_watchdog_register_device(dev, wdog);
-	if (ret)
-		return ret;
-
 	ret = imx_scu_irq_group_enable(SC_IRQ_GROUP_WDOG,
 				       SC_IRQ_WDOG,
 				       true);
 	if (ret) {
 		dev_warn(dev, "Enable irq failed, pretimeout NOT supported\n");
-		return 0;
+		goto register_device;
 	}
 
 	imx_sc_wdd->wdt_notifier.notifier_call = imx_sc_wdt_notify;
@@ -203,7 +224,7 @@ static int imx_sc_wdt_probe(struct platform_device *pdev)
 					 false);
 		dev_warn(dev,
 			 "Register irq notifier failed, pretimeout NOT supported\n");
-		return 0;
+		goto register_device;
 	}
 
 	ret = devm_add_action_or_reset(dev, imx_sc_wdt_action,
@@ -213,32 +234,10 @@ static int imx_sc_wdt_probe(struct platform_device *pdev)
 	else
 		dev_warn(dev, "Add action failed, pretimeout NOT supported\n");
 
-	return 0;
-}
-
-static int __maybe_unused imx_sc_wdt_suspend(struct device *dev)
-{
-	struct imx_sc_wdt_device *imx_sc_wdd = dev_get_drvdata(dev);
-
-	if (watchdog_active(&imx_sc_wdd->wdd))
-		imx_sc_wdt_stop(&imx_sc_wdd->wdd);
-
-	return 0;
+register_device:
+	return devm_watchdog_register_device(dev, wdog);
 }
 
-static int __maybe_unused imx_sc_wdt_resume(struct device *dev)
-{
-	struct imx_sc_wdt_device *imx_sc_wdd = dev_get_drvdata(dev);
-
-	if (watchdog_active(&imx_sc_wdd->wdd))
-		imx_sc_wdt_start(&imx_sc_wdd->wdd);
-
-	return 0;
-}
-
-static SIMPLE_DEV_PM_OPS(imx_sc_wdt_pm_ops,
-			 imx_sc_wdt_suspend, imx_sc_wdt_resume);
-
 static const struct of_device_id imx_sc_wdt_dt_ids[] = {
 	{ .compatible = "fsl,imx-sc-wdt", },
 	{ /* sentinel */ }
@@ -250,7 +249,6 @@ static struct platform_driver imx_sc_wdt_driver = {
 	.driver		= {
 		.name	= "imx-sc-wdt",
 		.of_match_table = imx_sc_wdt_dt_ids,
-		.pm	= &imx_sc_wdt_pm_ops,
 	},
 };
 module_platform_driver(imx_sc_wdt_driver);